INFO: task syz-executor.0:4419 blocked for more than 143 seconds. Not tainted 5.15.182-syzkaller #0 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. task:syz-executor.0 state:D stack:21760 pid: 4419 ppid: 1 flags:0x00004006 Call Trace: context_switch kernel/sched/core.c:5030 [inline] __schedule+0x11b8/0x43b0 kernel/sched/core.c:6376 schedule+0x11b/0x1e0 kernel/sched/core.c:6459 wb_wait_for_completion+0x164/0x290 fs/fs-writeback.c:191 sync_inodes_sb+0x1b3/0x920 fs/fs-writeback.c:2770 sync_filesystem+0x16d/0x220 fs/sync.c:64 generic_shutdown_super+0x6b/0x300 fs/super.c:448 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x418/0x4d0 fs/namespace.c:1143 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7ff9002f6c07 RSP: 002b:00007ffc22049718 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007ff900350af2 RCX: 00007ff9002f6c07 RDX: 0000000000000000 RSI: 000000000000000a RDI: 00007ffc220497d0 RBP: 00007ffc220497d0 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc2204a890 R13: 00007ff900350af2 R14: 000000000001470a R15: 0000000000000003 Showing all locks held in the system: 5 locks held by kworker/1:1/23: 1 lock held by khungtaskd/27: #0: ffffffff8c11bea0 ( rcu_read_lock ){....}-{1:2} , at: rcu_lock_acquire+0x0/0x30 4 locks held by kworker/u4:3/155: #0: ffff8881427d0938 ( (wq_completion)writeback ){+.+.}-{0:0} , at: process_one_work+0x760/0x1000 kernel/workqueue.c:-1 #1: ffffc90001f67d00 ( (work_completion)(&(&wb->dwork)->work) ){+.+.}-{0:0} , at: process_one_work+0x7a3/0x1000 kernel/workqueue.c:2285 #2: ffff888079d6e650 ( sb_internal #2 ){.+.+}-{0:0} , at: xfs_bmapi_convert_delalloc+0x1f1/0xd90 fs/xfs/libxfs/xfs_bmap.c:4573 #3: ffff88806e1b00e8 ( &xfs_nondir_ilock_class ){++++}-{3:3} , at: xfs_bmapi_convert_delalloc+0x21e/0xd90 fs/xfs/libxfs/xfs_bmap.c:4578 5 locks held by kworker/1:2/1111: 2 locks held by getty/3934: #0: ffff88802c3ca098 ( &tty->ldisc_sem ){++++}-{0:0} , at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:252 #1: ffffc90002cd62e8 ( &ldata->atomic_read_lock ){+.+.}-{3:3} , at: n_tty_read+0x5ba/0x1a30 drivers/tty/n_tty.c:2158 2 locks held by syz-executor.0/4419: #0: ffff888079d6e0e0 ( &type->s_umount_key #51 ){+.+.}-{3:3} , at: deactivate_super+0xa0/0xd0 fs/super.c:365 #1: ffff8881471ae7d8 ( &bdi->wb_switch_rwsem ){+.+.}-{3:3} , at: bdi_down_write_wb_switch_rwsem fs/fs-writeback.c:362 [inline] , at: sync_inodes_sb+0x197/0x920 fs/fs-writeback.c:2768 ============================================= NMI backtrace for cpu 0 CPU: 0 PID: 27 Comm: khungtaskd Not tainted 5.15.182-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: dump_stack_lvl+0x168/0x230 lib/dump_stack.c:106 nmi_cpu_backtrace+0x397/0x3d0 lib/nmi_backtrace.c:111 nmi_trigger_cpumask_backtrace+0x163/0x280 lib/nmi_backtrace.c:62 trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline] check_hung_uninterruptible_tasks kernel/hung_task.c:212 [inline] watchdog+0xe0f/0xe50 kernel/hung_task.c:369 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Sending NMI from CPU 0 to CPUs 1: NMI backtrace for cpu 1 CPU: 1 PID: 1111 Comm: kworker/1:2 Not tainted 5.15.182-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Workqueue: xfs-buf/loop0 xfs_buf_ioend_work RIP: 0010:delay_tsc+0x57/0xc0 arch/x86/lib/delay.c:79 Code: 90 49 89 d7 49 c1 e7 20 49 09 c7 4d 29 f7 49 39 df 73 53 bf 01 00 00 00 e8 d6 8d 50 fd 65 8b 05 77 a1 01 7c 85 c0 74 1c f3 90 01 00 00 00 e8 2f 8c 50 fd e8 aa 6e a0 05 39 c5 75 0e 0f 01 f9 RSP: 0018:ffffc90004aff370 EFLAGS: 00000002 RAX: 0000000000000002 RBX: 0000000000000899 RCX: 0000000000000000 RDX: 000000000000007f RSI: ffffffff8a59a2a0 RDI: 00000000ffffffff RBP: 0000000000000001 R08: 0000000000000004 R09: 0000000000000003 R10: fffff5200095fe64 R11: 1ffff9200095fe64 R12: 000000000000270c R13: ffffffff963c7be8 R14: 0000007f81334b86 R15: 00000000000000f0 FS: 0000000000000000(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055cb18517168 CR3: 000000007da45000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: wait_for_xmitr+0xb9/0x260 drivers/tty/serial/8250/8250_port.c:2077 serial8250_console_putchar+0x1a/0x50 drivers/tty/serial/8250/8250_port.c:3310 uart_console_write+0xaa/0x100 drivers/tty/serial/serial_core.c:1981 serial8250_console_write+0xbb5/0xf80 drivers/tty/serial/8250/8250_port.c:3387 call_console_drivers kernel/printk/printk.c:-1 [inline] console_unlock+0xc86/0x1200 kernel/printk/printk.c:2744 vprintk_emit+0xc0/0x150 kernel/printk/printk.c:2274 _printk+0xcc/0x110 kernel/printk/printk.c:2299 print_hex_dump+0x1a5/0x260 lib/hexdump.c:285 xfs_hex_dump+0x39/0x50 fs/xfs/xfs_message.c:118 xfs_buf_verifier_error+0x1ba/0x290 fs/xfs/xfs_error.c:418 xfs_allocbt_read_verify+0x53/0xd0 fs/xfs/libxfs/xfs_alloc_btree.c:-1 xfs_buf_ioend+0x25c/0x6e0 fs/xfs/xfs_buf.c:1263 process_one_work+0x863/0x1000 kernel/workqueue.c:2310 worker_thread+0xaa8/0x12a0 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287